I might be able to help with this, I'm doing a projection in the summer involving 15 20k hd projectors displaying an image size of 300m. I'm not sure M8 is up to the task, i'll be doing some extensive tests.
i'm also coming to Barcelona in feb
1st thing your image resolution needs to be hd or the dot size will be huge
will you be using pre-made video work?
what brightness of projectors are you planning to use
i have access to Barco 20K projectors, the UK hire cost is a lot less than barcelona
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